1. Field of the Invention:
The invention generally relates to a robotic arm and, more particularly, to a remotely controllable robotic arm which provides work access to the interior of a nuclear vessel through a small diameter opening thereto and wherein six axes of motion are powered by servo motors outside of the nuclear vessel to be remote from a hostile environment within the nuclear vessel.
2. Description of the Prior Art:
In performing maintenance on a nuclear vessel, such as a large tank, it may be necessary to perform operations within the vessel, such as grinding and welding. One way to achieve access to the interior of the nuclear vessel has been to cut a large diameter hole in the wall thereof to permit man entry, with this being a time-consuming operation and exposing service personnel to a hostile environment. It has also been known to insert a tool-holding device through a tube at the top of the vessel and operate the device through a limited number of axes of motion manually by an operator. The operator is positioned at the top of the vessel and sights the tool through a mirror system and causes motion thereof by operation of cranks connected to cables.
Industrial robots are well known commercially-available structures. However, such robots have not had the desired axes of remotely-controlled motion, nor the size to enable insertion within a relatively small diameter hole at the top of a nuclear vessel to perform work operations within the nuclear vessel.